One of the victims Cesar Rodriguez, 18, collapsed in front of his home Thursday while riding his bike and running around. He died later that day. His family said that he had no known medical conditions but may have not consumed enough water.

The most recent report from the National Weather Service said that at least 22 people had died because of the extreme heat and humidity. Emergency rooms reported Thursday that they were "stacked up" with patients.

"We're up in overall cases by 10 percent every day this week," the Detroit Medical Center told ABC News. "The chief of emergency medicine estimated that 15 percent to 20 percent are heat exhaustion or heat-related cases."

U.S. Power Grid Under Stress

The nation's power grid is under tremendous stress from the so-called heat dome, which is a shroud of high pressure that is trapping and compressing hot, humid air from the Gulf of Mexico, with at least one city already resorting to intentional blackouts.

New York City's Consolidated Edison pleaded today for customers to use less electricity as New York City and Westchester County blew past their records for power consumption this afternoon. Small power outages were reported today, but most were back on line. Temperatures reached 102 with a heat index of 116.

In Chicago, Commonwealth Edison reached an all-time peak usage milestone late Wednesday, while ISO New England – which covers six states from Connecticut to Maine -- forecasts that demand Saturday will peak at 27,350 megawatts, putting it in the top 10 of usage days.

Intentional rolling blackouts have already begun in the Detroit area.

The worst day for the heat index is yet to come for the East Coast and the Mid-Atlantic region -- from North Carolina to New York -- where heat index values could exceed 115 degrees.

Half of the country is under a heat advisory, although the East Coast might have a slight break in the not-too-distant future.

Heat Relief on Its Way?

According to senior forecaster Michael Eckerdt at the National Weather Service, the 100-plus degree temperatures might take a dip later this weekend.

"There is a cold front that is going to be dropping into the eastern U.S. this weekend," Eckerdt said. "The heat will continue into Saturday and then we will see moderating temperatures back down into around the 90-degree range as we move into Sunday and Monday. But it's going to still remain very warm."

"The cities of New York City, Philadelphia, Baltimore, Washington down toward Richmond and Raleigh are really going to feel the heat Friday afternoon," Eckerdt said.

Heat and humidity combined for a heat index of 121 at Dulles Airport in the Washington, D.C., area while it hit 112 as far north as Syracuse, New York, Thursday, when there were 141 million people across the United States in more than two dozen states under heat advisories.